Progressive flexibility catheter support frame

ABSTRACT

Cut-pattern designs creating a frame structure from a solid tube, which may be used as a portion of medical device, such as a catheter. The tube includes a plurality of units of cutout segments which are distributed in band around a circumference of the tube. A tube can have multiple different zones, each having units with varying cutout segments. The cutout segments can have varying cutout surface area allowing the flexibility of the tube to be modified at any point along the tube by altering the cutout surface area with zones having greater cutout surface areas as compared to another zone are more flexible. The tube can be incorporated into a catheter.

CROSS REFERENCE TO RELATED APPLICATION

This application claims priority to U.S. Provisional Application No.62/075,177, filed Nov. 4, 2014, and U.S. Provisional Application No.62/238,428, filed Oct. 7, 2015, the disclosures of which areincorporated by reference herein in their entirety.

FIELD OF THE INVENTION

The invention relates to a series of cut-pattern designs which create aframe structure from a solid tube and which may be used as a portion ofmedical device, such as a catheter.

BACKGROUND

In coronary artery disease, the coronary arteries may be narrowed oroccluded by atherosclerotic plaques or other lesions. These lesions maytotally obstruct the lumen of the artery or may dramatically narrow thelumen of the artery. In order to diagnose and treat obstructive coronaryartery disease it is commonly necessary to pass a guidewire or otherinstruments through and beyond the occlusion or stenosis of the coronaryartery.

Percutaneous coronary intervention (PCI), also known as coronaryangioplasty, is a therapeutic procedure used to treat the narrowed orstenotic section of the coronary artery of the heart due to coronarylesions or obstructions. A guide catheter may be used in PCI to providesupport an easier passage for another catheter or device (microcatheter,stents, balloons, etc.) to access the target site. For example, a guidecatheter can be inserted through the aorta and into the ostium of thecoronary artery. Once seated in the opening or ostium of the artery tobe treated, a guidewire or other instrument is passed through the lumenof the guide catheter and then inserted into the artery distal to theocclusion or stenosis. Another example for the use of a guide catheteris shown where the guide catheter can be inserted through the aorta andinto the peripheral anatomy enabling access, for example, to the femoralartery down through the popliteal artery. This procedure allows foraccess to vasculature below the knee.

However, guide catheters may encounter certain difficulties. The anatomyin the area for placement, e.g., the coronary vasculature, may betortuous and the lesions themselves may be comparatively non-compliant.Moreover, when crossing comparatively non-compliant lesions, a backwardforce sufficient to dislodge the guide catheter from the ostium of theartery being treated can be generated. For example, in order to improvebackup support, U.S. Re. 45,830, assigned to Vascular Solutions, Inc.,discloses a coaxial guide catheter which is adapted to be passablewithin a guide catheter. The distal portion of the coaxial guide can beextended distally from the distal end of the guide catheter. The coaxialguide catheter includes a flexible tip portion defining a tubularstructure having a lumen through which interventional cardiology devicessuch as stents and balloons can be inserted and a substantially rigidportion proximal of and more rigid than the flexible tip portion thatdefines a rail structure without a lumen.

Facilitating equipment delivery is the most common indication for usinga guide catheter. Other indicates include, thrombectomy, facilitatinginterventions in chronic total occlusion (CTO)s and selective contrastinjection into the vasculature. Duaong et al. J. Invasive Cardiol27(10):E211-E215 (2015).

As illustrated in FIG. 1A, which is a depiction of a commercial product“Guideliner®” from Vascular Solutions, Inc., a guide catheter extension100 includes a distal portion 110 having a full circumference, ahalf-pipe portion 120, a collar transition 115 which provides arapid-exchange type access point to insert interventional devices (e.g.,balloons, stents, etc.), a push rod 130, and a proximal tab 140 formanual manipulation of the guide catheter extension 100.

Another device is Guidezilla® from Boston Scientific Corp. FIG. 1Bdepicts a commercial guide catheter extension product. Compared to FIG.1A, this product lacks an explicit half-pipe section, and instead uses askived or tapered collar transition which is directly connected to apush rod or rail.

To date the guide catheter extension devices disclosed or availablerequires construction of different tube portions of differentcharacteristics and joining these tube portions together. For example,as disclosed in U.S. Re 45,830, the catheter extension includes a softtip, a reinforced portion that is made of braided or coil reinforcedpolymeric section (e.g., PTFE (polytetrafluoroethylene) (liner and Pebaxas the exterior), and a substantially rigid portion which may be made ofstainless steel or nitinol tube. For the Guidezella® catheter, thecollar transition is made of a different material than the tubularportion which has a reinforced portion formed from multi-filamentbraided wire to reinforced the polymeric section. This structure makesfabrication complicated.

Prior art designs for catheter tube bodies that have varying degrees offlexibility along the long or longitudinal axis often employ spiral cutsor interrupted spiral cuts along part of the tube segment. Parameters ofthe spiral cuts, such as cut pitch angle, cut widths, cut lengths, etc.,are varied in order to provide the varying degrees of flexibility to thecatheter shaft.

However, there remains a need for improved design for catheterextensions, and more generally, alternative designs for catheter tubes,that allow not only ease of fabrication, but also control of variouscharacteristics of the tube, e.g., steerability, variable bendingflexibility along the working length, pushability, collapse or kinkresistance, etc., at any point along the tube.

SUMMARY OF THE INVENTION

The invention provides for a tube, comprising, at least one zonepositioned along a portion of the length of the tube, the zonecomprising a plurality of units, where the units of the zone aredistributed circumferentially around the tube in at least one firstband, each unit of the zone comprises at least one cutout segment thatis oriented around a center of symmetry, where the center of symmetry ofeach unit in the band is positioned equally from the center of symmetryof an adjacent unit in the same band and the center of symmetry of eachunit is positioned at the same point on the circumference of the tube asthe center of symmetry of a second unit in a third band which isseparated by one band from the first band. The tube could have 2-100zones and there can be 2-1000 bands in each zone.

In one embodiment, the unit comprises three cutout segments extendingradially from a center of symmetry of the unit, where each cutoutsegment of the unit is positioned 120° degrees from the other cutoutsegments in the unit in the band. In this three cutout embodiment, therecan be seven zones, a first zone, a second zone, a third zone, a fourthzone, a fifth zone, a sixth zone and a seventh zone, each zone is formedfrom a plurality of units, where rank order of cutout surface area andcut-pattern perimeter length is: units of the first zone<unit of thesecond zone<unit of the third zone<unit of the fourth zone<unit of thefifth zone<unit of the sixth zone<unit of the seventh zone. The zonescan be arranged in sequence as first zone, second zone, third zone,fourth zone, fifth zone, sixth zone and seventh zone.

Alternatively, the cutout segments are in the shape of a hexagon. Thishexagon cutout embodiment can have seven zones, a first zone, a secondzone, a third zone, a fourth zone, a fifth zone, a sixth zone and aseventh zone, each zone is formed from a plurality of units, where rankorder of cutout surface area and cut-pattern perimeter length is: unitof the first zone<unit of the second zone<unit of the third zone<unit ofthe fourth zone<unit of the fifth zone<unit of the sixth zone<unit ofthe seventh zone.

The tube can be made from a metallic material, such as nitinol orstainless steel.

The tube can further comprise a section which has a spiral cut sectionalong a portion of the length of the tube and the spiral cut section canbe contiguous with the zone of the tube. The spiral cut section may bean interrupted spiral cut.

In another embodiment, the cutout segments are in the shape of a circle.

The invention comprises a guide catheter extension comprising: a tubecomprising, at least one zone along a portion of the length of the tube,the zone comprising a plurality of units, where the units of the zoneare distributed circumferentially around the tube in at least one band,each unit of the zone comprises at least one cutout segment that isoriented around a center of symmetry, where the center of symmetry ofeach unit in the band is positioned equally from the center of symmetryof an adjacent unit in the same band; a skived collar transition sectiondisposed adjacent the tube, the transition section having a taperededge, a short end and a long end; and a push rod attached at the longend of the transition section. In this embodiment, each unit comprisesthree cutout segments extending radially from a center of symmetry ofthe unit, where each cutout segment of the unit is positioned 120°degrees from the other cutout segments in the unit in the band. The tubecan comprise seven zones, a first zone, a second zone, a third zone, afourth zone, a fifth zone, a sixth zone and a seventh zone, each zonehaving is formed from a plurality of units, wherein rank order of cutoutsurface area and cut-pattern perimeter length is: unit of the firstzone<unit of the second zone<unit of the third zone<unit of the fourthzone<unit of the fifth zone<unit of the sixth zone<unit of the seventhzone. The zones can be arranged in sequence as first zone, second zone,third zone, fourth zone, fifth zone, sixth zone and seventh zone.

In another embodiment, the cutout segments are in the shape of a hexagonin tube of the guide catheter extension.

In a further embodiment, the guide catheter extension can comprise: atube comprising, at least one zone along a portion of the length of thetube, the zone comprising a plurality of units, where the units of thezone are distributed circumferentially around the tube in at least oneband, each unit of the zone comprises at least one cutout segment thatis oriented around a center of symmetry, where the center of symmetry ofeach unit in the band is positioned equally from the center of symmetryof an adjacent unit in the same band; a flared bib, that issubstantially perpendicular to the long axis of the tube, which has agreater diameter than the outer diameter of the tube; and, a push rodattached at the long end of the transition section.

In various embodiments, the diameter of the tube can taper from aproximal end to a distal end.

The tube of the guide catheter extension can further comprise a sectionwhere the tube has a spiral cut section along a portion of the length ofthe tube and the spiral cut section is contiguous with the zone of thetube. The spiral cut section can be an interrupted spiral cut.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A depicts a prior art catheter extension device.

FIG. 1B depicts another prior art catheter extension device.

FIG. 2A is an unrolled or flat view of a tube having triplex cutpatterns according to some embodiments of the present invention.

FIG. 2B is another unrolled or flat view of a tube having triplex cutpatterns as depicted in FIG. 2A, which includes 7 triplex zones (Zone 1to Zone 7).

FIG. 2C is another unrolled or flat view of a tube in FIG. 2A.

FIG. 2D is another unrolled or flat view of a tube in FIG. 2C showingthe center of symmetry across the tube.

FIG. 3A shows the details of the unit in zone 1.

FIG. 3B shows cutout perimeter of the unit in zone 1.

FIG. 4A shows the details of the unit in zone 2.

FIG. 4B shows cutout perimeter of the unit in zone 2.

FIG. 5A shows the details of the unit in zone 3.

FIG. 5B shows cutout perimeter of the unit in zone 3.

FIG. 6A shows the details of the unit in zone 4.

FIG. 6B shows cutout perimeter of the unit in zone 4.

FIG. 7A shows the details of the unit in zone 5.

FIG. 7B shows cutout perimeter of the unit in zone 5.

FIG. 8A shows the details of the unit in zone 6.

FIG. 8B shows cutout perimeter of the unit in zone 6.

FIG. 9A shows the details of the unit in zone 7.

FIG. 9B shows cutout perimeter of the unit in zone 7.

FIG. 10A-10H show the transition across zones 1 to 7.

FIG. 11A shows the cutout for a tube composed of zone 1.

FIG. 11B shows the cutout for a tube composed of zone 3.

FIG. 11C shows the cutout for a tube composed of zone 4.

FIG. 11D shows the cutout for a tube composed of zone 5.

FIG. 11E shows the cutout for a tube composed of zone 6.

FIG. 11F shows the cutout for tube composed of zones 1, 3, 5, 5 and 6.

FIG. 12A shows further details for the unit of zone 7.

FIGS. 12B, 12C show photomicrographs with a reduction in width (strutwidth) from 10%, and 50%, respectively.

FIG. 13 is an unrolled plan view of a tube having hybrid cut patternsincluding a spiral cut section and a section having a triplex cutpattern, according to one embodiment of the present invention.

FIG. 14A is a side cross sectional view of a portion of a guide catheterextension including multiple triplex pattern zones according to oneembodiment of the present invention.

FIG. 14B is an unrolled or flat view of a portion of a guide catheterextension including a single triplex pattern zone according to oneembodiment of the present invention.

FIG. 14C is a photo of the portion of the guide catheter extensionhaving the cut-pattern shown in FIG. 14B.

FIG. 14D shows a detail of a portion of FIG. 14B having transverse cuts.

FIG. 15A is a schematic side view of a guide catheter extension having agenerally longitudinal cut according to certain embodiments of thepresent invention.

FIG. 15B is a schematic top view of the guide catheter extension shownin FIG. 15A.

FIG. 15C is a schematic top view of the guide catheter extension whensplit open along the longitudinal cut shown in FIGS. 15A and 15B.

FIG. 15D is a 3D rendering of the guide catheter extension in 15A.

FIG. 15E is a 3D rendering of a top down view the guide catheterextension in 15D.

FIG. 15F is a 3D rendering of a side view the guide catheter extensionin 15D.

FIG. 16A shows certain components of a distal portion of a catheteraccording to an embodiment of the present invention.

FIG. 16B shows the distal portion as assembled from the components shownin FIG. 16A.

FIG. 16C shows a partial sectional view of the distal portion asdepicted in FIG. 16B.

FIGS. 16D-16E show partial sectional views of various parts of thedistal portion as depicted in FIG. 16B.

FIGS. 16F-16G show partial sectional views of various parts of thedistal portion of a catheter according to an embodiment of the presentinvention.

FIG. 17A shows a guide catheter extension having an attached sealeraccording to one embodiment of the present invention.

FIG. 17B-17D show various configurations of a sealer according tocertain embodiments of the present invention.

FIG. 18A is a schematic side view of a guide catheter extension havingan end with a flared bib contained in a guide catheter, according tosome embodiments of the present invention.

FIG. 18B is a cross-sectional view of the guide catheter extension andthe guide catheter depicted in FIG. 18A.

FIG. 19 depicts a guide catheter extension having a skived collartransition section with a flared bib and a tube portion having varyingdiameter.

FIG. 20 shows the guide catheter assembly with an assembled handle.

DETAILED DESCRIPTION

The present invention generally relates to multiple cut-pattern designsfor a tubular structure (or tube) of a medical device for interventionalprocedures that can be passed through a portion of a patient'svasculature or into other body lumens, such as guiding catheters, guidecatheter extensions, micro-catheters, as well as other catheter tubes. Atube (or a portion thereof) may be substantially uniform in diameteracross its entire length. Alternatively, the tube can have a varyingdiameter across its length, e.g., a tapered configuration. The taperingcan be in any direction and may only be present along a portion of thetube. The tube can be made from a metallic material (e.g., stainlesssteel) or metal alloy, for example, a shape memory material such asnitinol which renders the tube kink resistant. Alternatively, the tubecan be formed from polymers, glass filled polymers or a metal-polymercomposite. The exterior surface of tube, which can have the desired cutor etched patterns, can be further encapsulated or covered with apolymeric jacket material, and the inner surface of the tube can belined with a polymer inner lining which has a smooth, lubricous surface.

One embodiment of the tube cut patterns of the invention is shown inFIGS. 2A and 2B. A tube 200 having a longitudinal axis 203 (L), aproximal end 201, a distal end 202, and a body or tube wall. The tubewall has cut patterns which include a plurality of zones, 1-7, which arearranged along the longitudinal axis L. The zones can be along anyportion of the tube or a single zone may comprise the entire tube. Thelength of the tube is shown as LA. Each zone includes a plurality ofunits (or groups) of radially symmetric, cutout segments that aredistributed around the circumference of the tube in a band or row. Aband or row can have 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 30, 40, 50, 60, 70,80, 90, 100, 200, 300, 400, 500, 1000 to n units. In FIGS. 2A and 2Bthere are 5 units in each band or row. The number of units per band orrow may be the same or different in two different zones. As shown inFIG. 2B, a unit from each of the 7 zones is identified as 210, 220, 230,240, 250, 260, 270, respectively. Each unit of the cutout portions caninclude three cutout segments each segment extending radially from acenter point or center of symmetry. The cutout segments have athree-fold rotational symmetry, where each cutout segment is rotated 120degrees from an adjacent cutout segment about a center of symmetry.Within each zone, all of the units of cutout segments may have an equalopen surface area (i.e., the open surface area is the area enclosed bythe contour of the segments in a contiguous manner) as well as an equalcut-pattern perimeter length, the length of a continuous line tracedalong the shape of the cutout segment. Across different zones, the unitsof cutout segments may have larger surface areas and increasedcut-pattern perimeter length in zones when labeled in the figure withhigher zone numbers, e.g., the open surface area ranking unit of zone1<unit of zone 2<unit of zone 3<unit of zone 4<unit of zone 5<unit ofzone 6<unit of zone 7 and the cut-pattern perimeter length ranking isunit of zone 1<unit of zone 2<unit of zone 3<unit of zone 4<unit of zone5<unit of zone 6<unit of zone 7. The patterns of the cutout portionshaving the three-fold rotational symmetry about a central point ofsymmetry (center of symmetry) as shown can also generally referred to asthe “triplex” pattern or “triplex” cut herein.

In FIG. 2A-2B, the triplex zones 1-7 are shown as being arrangedsequentially along the longitudinal axis 203 of the tube having a lengthLA. The configuration shown provides for a gradually decreasing uncutsurface area coverage along the length of the tube from the proximal end201 to the distal end 203, enabling the tube 200 to have a graduallyincreasing bending flexibility from the proximal end 201 to the distalend 203. The 7 zones in FIG. 2B are shown arranged in sequence, i.e., 1to 7, only for illustrative purpose. In other embodiments, the zonescontaining the units can be arranged in any order along the longitudinalaxis to provide any desired change of bending flexibility at any pointor section along the longitudinal axis. The tube can be provided withfewer, 1, 2, 3, 4, 5 or 6, or more zones, 7, 8, 9, 10, 11, 12, 13, 14 or15 (higher numbers are also possible, e.g. 20, 30, 40, 50, 60, 70, 80,90, 100, 200, 300, 400, 500, 600, 700, 800, 900, 1000 to n differentzones). The zones, which have different cutout surface areas as well asdifferent cut-pattern perimeter lengths, can also be arranged in anyorder, e.g., zone 1, zone 6, zone 7, zone 4, zone 5, zone 3, zone 2, inorder to control flexibility of the tube at any point along the lengthof the tube.

As shown in FIGS. 2A-2B, each of zones 1-5 can include two adjacent rowsor bands (as used herein, the term, row or rows is used interchangeablywith the term band or bands) of units of cutout segments (e.g., bands inzone 1 and bands in zone 2 are shown as 204, 205 and 206, 207,respectively, FIG. 2A) each arranged around the circumference of thetube. The rows or bands may also be referred to as circumferential rowsor bands. In a row or band, the units are distributed in a straight linearound the circumference of the tube. For illustration only, the bandcomprising the units of zone 1 and zone 2 are shown with a dotted linethrough the center of each band intersecting the center of symmetry (Cs)for each unit; for zone 1, the dotted lines are 204 and 205, while forzone 2, the dotted line is 206 (FIG. 2A). Other numbers of bands/rows ofunits in a zone are also possible, including, 1, 2, 3, 4, 5, 6, 7, 8, 9,10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 200, 300, 400, 500, 1000 up ton bands or rows.

The spacing between units in a band is shown in FIG. 2A and isrepresented as dc, where dc is the distance between the center ofsymmetry, Cs, of two adjacent units in the same band (see, e.g., 204).The spacing, dc, is equal within a single band and may be constantacross the length of the tube in different zones. The spacing betweenbands within a zone, e.g., zone 1, zone 2 and zone 3, is shown as d1(204-205), d2 (206-207) and d3 (208-209); d1=d2=d3, where the spacing ismeasured between the lines, 204, 205, 206, 207, 208 and 209, which runthrough the center of symmetry, Cs, of the bands within each zone. Thespacing between zones, e.g., zone 1-zone 2, d12 (205-206), zone 2-zone3, d23 (207-208) and zone 3-zone 4, d34 (209-211); d12=d23=d34, wherethe spacing is measured between the lines, 204, 205, 206, 207, 208, 209and 211. In one embodiment, the spacing between bands within a zone maybe equal to the spacing of two bands between two different zones, e.g.,d1=d2=d3=d12=d23=d34. In other embodiments, the spacing between bandswithin a zone may be greater than or less than the spacing between thebands in two different zones, e.g., d1=d2=d3>d12=d23=d34 ord1=d2=d3<d12=d23=d34.

The overall arrangement of one embodiment of the tube is shown in FIG.2B. The boundaries of each zone are shown as follows: zone 1, 212, 213,zone 2, 214, 215, zone 3, 216, 217, zone 4, 218, 219, zone 5, 221, 222,zone 6, 223, 224 and zone 7, 225, 226. The boundaries of the zonesoverlap with each other. The units within each zone are shown as zone 1,210, zone 2, 220, zone 3, 230, zone 4, 240, zone 5, 250, zone 6, 260 andzone 7, 270.

As shown in FIG. 2A-2C, all cutout segments of the units within a zonecan have the same orientation or are in-phase with respect to the linethrough the center of symmetry for each row, 204 and 205; compare cutoutsegments 231-232, 233-234 and 235-236. The cutout segments in adjacentbands or rows within a zone can also have the same orientation or arein-phase with respect to the line through the center of symmetry foreach row, 204 and 205; compare, 231-237 and 235-238. In other words, thecorresponding cutout segments in one unit within a zone are parallelwith the cutout segments in an adjacent unit. The center of symmetry,Cs, of units within the same zone, but in adjacent bands is shifted byone unit as shown in FIG. 2C. Between two adjacent zones, e.g., zone 1and zone 2, the units are shifted around the circumference of the bandsuch that a straight line, 239, can be drawn between the center ofsymmetry for units in the same zone or adjacent zones in every otherband, e.g., 1, 3, 5, 7, etc. bands. The center of symmetry, Cs, indifferent bands falls along the same line in every other band. FIG.2D—reference lines 281 and 282. In other words, the center of symmetryof each unit is positioned at the same point on the circumference of thetube as the center of symmetry of a second unit in a third, third,fifth, etc. band which is separated by one band from the first band.

Depending on the material as well as the structural requirements interms of flexibility, the thickness of the tube at any point can vary,e.g., from about 0.05 mm to 2 mm, e.g., 0.05 mm to about 1 mm, about 0.1mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1.0mm, etc. The inner diameter of the lumen (ID) of the tube portion canvary, e.g., from about 0.1 mm to about 2 mm, or from about 0.25 mm toabout 1 mm, e.g., about 0.2 mm, about 0.3 mm, about 0.4 mm, about 0.5mm, about 0.6 mm, about 0.7 mm, about 0.8 mm, about 0.9 mm, about 1 mm,etc. The outer diameter of the lumen (OD) of the tube can also vary,e.g., from about 0.2 mm to about 3 mm, e.g., about 0.2 mm, about 0.3 mm,about 0.4 mm, about 0.5 mm, about 0.6 mm, about 0.7 mm, about 0.8 mm,about 0.9 mm, about 1 mm, about 1.1 mm, about 1.2 mm, about 1.3 mm,about 1.4 mm, about 1.5 mm, about 1.6 mm, about 1.7 mm, about 1.8 mm,about 1.9 mm, about 2.0 mm, etc. The thickness of the tube wall, theinner diameter ID and the outer diameter OD can each be constantthroughout the length of the tube, or vary along the length of the tube.

FIGS. 3A, B-9A, B show a close-up image of units from zones 1-7. Theunits in these figures are shown only as cutout segments, withoutoverlapping units from other zones as is the case when the cutoutsegments are present in the tube (tube wall). FIG. 3A shows the unitfrom zone 1 with 3 cutout segments 303, 304 and 305. The cutout segmentmaybe formed by two linear portions 309 a, 309 b, capped by twocurvilinear portions 307 and 311. The curvilinear portions begin atpositions 308 and 310, respectively for cutout segment 300. In oneembodiment, the width of the cutout 306 divided by 2 equals the radiusof the curvilinear portions 307, 311. The open surface area of thecutout segments 303, 304 and 305 is 300, 301 and 302, respectively. Inthe embodiment shown, the cutout segments, 303, 304 and 305 arepositioned equally from the center of symmetry, Cs, 312 by a distanceequal to the width 306 divided by 2. In other words, an imaginary circle313 may be positioned between the cutout segments having a radius equalto the width of the cutout segment 306/2. The cut-pattern perimeterlength of the cutout pattern from zone 1 is shown in FIG. 3B and is thesum of perimeters of each of the three cutout segments, 314+315+316.

FIG. 4A shows the unit from zone 2. The cutout zone 407 is composed ofthree contiguous cutout segments 400, 401, 402 which have been mergedinto a single cutout pattern having an open surface area of 407. Eachcutout segment is composed of two, equal linear portions, 405 a, 405 b,and a curvilinear portion 404 starting at position 403. The center ofsymmetry, Cs, for the unit is shown as 406. The linear portions of eachcutout segment are connected by a curvilinear portion 408; specifically,in the embodiment shown, the linear portion of cutout segment 400, 405b, is connected by a curvilinear portion 408 to the linear portion 409 aof the cutout segment 401. The radius of curvature of the curvilinearportions 404 and 408 can vary. The width, i.e., the distance between thetwo linear portions 405 a, 405 b can be equal to, less than or greaterthan the width between the two linear portions shown in zone 1, 306. Thecut-pattern perimeter length of the cutout pattern from zone 2 is shownin FIG. 4B and is 411.

FIG. 5A shows the unit from zone 3. The center of symmetry of the unitis shown as 500 is composed of three contiguous, cutout segments 501,502, 503 having an open surface area 514. Each cutout segment iscomposed of two linear portions 504 a, 504 b, and a curvilinear portion506, 516 starting at position 507. The open surface area of thecurvilinear portion is shown in cross hatch as 513. The shape of thecurvilinear portion 506 can vary and only one embodiment is shown in thefigure. The cutout segments are connected by a curvilinear portion 512starting at position 508. As illustrated in the figure, the two equal,linear portions 504 a and 511 b are connected by a curvilinear portion512; the degree of curvature of the curvilinear portion 512 can vary.The width of the 515 between the two linear portions 504 a, 504 b can beequal to, less than or greater than the width of the between the twolinear portions 410 in zone 2, FIG. 4a . The length of the linearportions 504 a, 504 b is less than, equal to or the greater than thelinear portions in zone 2, 405 a, 405 b. In the embodiment shown thelinear portions 504 a=504 b<405 a=405 b. The cut-pattern perimeterlength of the cutout pattern from zone 3 is shown in FIG. 5B and is 517.

FIG. 6A shows the unit from zone 4. The center of symmetry, Cs, of theunit is shown as 600 is composed of three contiguous, cutout segments601, 602, 603 having an open surface area 614. Each cutout segment iscomposed of two linear portions 604 a, 604 b, and a curvilinear portion606, starting at position 607. The open surface area of the curvilinearportion is shown in cross hatch as 613. The shape of the curvilinearportion 606 can vary and only one embodiment is shown in the figure. Thecutout segments are connected by a curvilinear portion 612 starting atposition 608. As illustrated in the figure, the two equal, linearportions 604 a and 604 b are connected by a curvilinear portion 612; thedegree of curvature of the curvilinear portion 612 can vary. The widthof the 615 between the two linear portions 604 a, 604 b can be equal to,less than or greater than the width of the between the two linearportions 515 in zone 3, FIG. 5a . The length of the linear portions 604a, 604 b is less than, equal to or the greater than the linear portionsin zone 3, 505 a, 505 b. In the embodiment shown the linear portions 604a=604 b<505 a=505 b. The cut-pattern perimeter length of the cutoutpattern from zone 4 is shown in FIG. 6B and is 616.

FIG. 7A shows the unit from zone 5. The center of symmetry, Cs, of theunit is shown as 700 is composed of three contiguous, cutout segments701, 702, 703 having an open surface area 714. Each cutout segment iscomposed of two linear portions 704 a, 704 b, and a curvilinear portion706, starting at position 707. The open surface area of the curvilinearportion is shown in cross hatch as 713. The shape of the curvilinearportion 706 can vary and only one embodiment is shown in the figure. Thecutout segments are connected by a curvilinear portion 712 starting atposition 708. As illustrated in the figure, the two equal, linearportions 704 a and 704 b are connected by a curvilinear portion 712; thedegree of curvature of the curvilinear portion 712 can vary. The widthof the 715 between the two linear portions 704 a, 704 b can be equal to,less than or greater than the width of the between the two linearportions 615 in zone 4, FIG. 6a . The length of the linear portions 704a, 704 b is less than, equal to or the greater than the linear portionsin zone 4, 605 a, 605 b. In the embodiment shown the linear portions 704a=704 b<605 a=605 b. The cut-pattern perimeter length of the cutoutpattern from zone 5 is shown in FIG. 7B and is 716.

FIG. 8A shows the unit from zone 6. The center of symmetry, Cs, of theunit is shown as 800 is composed of three contiguous, cutout segments801, 802, 803 having an open surface area 814. Each cutout segment iscomposed of two linear portions 804 a, 804 b, and a curvilinear portion806, starting at position 807. The open surface area of the curvilinearportion is shown in cross hatch as 813. The shape of the curvilinearportion 706 can vary and only one embodiment is shown in the figure. Thecutout segments are connected by a curvilinear portion 812 starting atposition 808. As illustrated in the figure, the two equal, linearportions 804 a and 804 b are connected by a curvilinear portion 712; thedegree of curvature of the curvilinear portion 712 can vary. The widthof the 815 between the two linear portions 804 a, 804 b can be equal to,less than or greater than the width of the between the two linearportions 715 in zone 5, FIG. 7a . The length of the linear portions 804a, 804 b is less than, equal to or the greater than the linear portionsin zone 5, 705 a, 705 b. In the embodiment shown the linear portions 804a=804 b<705 a=705 b. The cut-pattern perimeter length of the cutoutpattern from zone 6 is shown in FIG. 8B and is 816.

FIG. 9 shows the unit from zone 7. The center of symmetry, Cs, of theunit is shown as 900 is composed of three contiguous, cutout segments901, 902, 903 having an open surface area 914. Each cutout segment iscomposed of two linear portions 904 a, 904 b, and a curvilinear portion906, starting at position 907. The open surface area of the curvilinearportion is shown as a cross hatch 913. The shape of the curvilinearportion 906 can vary and only one embodiment is shown in the figure. Thecutout segments are connected by a curvilinear portion 912 starting atposition 908. As illustrated in the figure, the two equal, linearportions 904 a and 911 b are connected by a curvilinear portion 912; thedegree of curvature of the curvilinear portion 912 can vary. The widthof the 915 between the two linear portions 904 a, 904 b can be equal to,less than or greater than the width of the between the two linearportions 815 in zone 6, FIG. 8a . The length of the linear portions 904a, 904 b is less than, equal to or the greater than the linear portionsin zone 6, 805 a, 805 b. In the embodiment shown the linear portions 904a=904 b<805 a=805 b. The cut-pattern perimeter length of the cutoutpattern from zone 7 is shown in FIG. 9B and is 916.

An overview of the transition of the units across zone 1 to zone 7 isshown in FIGS. 10A-10H. The following characteristics apply to thedimensions across the zones. The open surface area of the cutout areasacross the different zones rank orders as:(300+301+302)<407<514<614<714<814<914. The rank order of the opensurface area of the curvilinear portion is: 513<613<713<813<913. Therank of the linear portions is: 904 a=904 b<805 a=805 b<704 a=704 b<605a=605 b<505 a=505 b. The rank order of the cut-pattern perimeter lengthsis (314+315+316)<411<517<616<716<816<916. The change in either opensurface area or cut-pattern perimeter length across multiple zones canbe linear, exponential, assume a step-wise or square wave function andbe increasing, decreasing, constant, continuous or discontinuous.

Within any one zone, the cutout segments forming a unit may assume anysymmetrical shape about a center of symmetry, Cs. There may be 1, 2, 3,4, 5, 6, 7, 8, 9, 10 or n cutout segments in a unit. The cutout segmentsmay be continuous or separate. For example, the cutout segment may forma circle or a symmetrical, n-sided polygon, such as a hexagon oroctagon. Different zones may have the same or different symmetricalshapes. The geometric rules, both within a zone as well as across a zoneremain the same in these embodiments as they are for the triplex cutoutsegments described above. Specifically, the units are arranged in aband. A band or row can have 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 30, 40, 50,60, 70, 80, 90, 100, 200, 300, 400, 500, 1000 to n units. The spacingbetween units in a band represented as dc, where dc is the distancebetween the center of symmetry, Cs, of two adjacent units in a band, dc,is equal within a single band and may be constant across the length ofthe tube in different zones. The spacing between bands within a zone andacross zones may be equal as well. All cutout segments of the unitswithin a zone can have the same orientation or are in-phase with respectto the line through the center of symmetry for each row or band. Thecutout segments in adjacent bands or rows within a zone can also havethe same orientation or are in-phase with respect to the line throughthe center of symmetry for each row. The center of symmetry, Cs, ofunits within the same zone, but in adjacent bands is shifted. Betweentwo adjacent zones, the units are shifted around the circumference ofthe band such that a straight line can be drawn between the center ofsymmetry for units in adjacent zones. The center of symmetry, Cs, indifferent bands falls along the same line in every other band. In otherwords, the center of symmetry of each unit is positioned at the samepoint on the circumference of the tube as the center of symmetry of asecond unit in a third, third, fifth, etc. band which is separated byone band from the first band.

One tube may contain multiple zones. For example, the tube can beprovided with 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14 or 15(higher numbers are also possible, e.g. 20, 30, 40, 50, 60, 70, 80, 90,100, 200, 300, 400, 500, 600, 700, 800, 900, 1000 to n different zones).If a tube contains multiple zones, then across different zones there maybe a change in open surface area and cut-pattern perimeter length. Forexample, if the cutout segment is formed in the shape of a hexagon andthere are seven zones, a first zone, a second zone, a third zone, afourth zone, a fifth zone, a sixth zone and a seventh zone, then therank order for the open surface area and cut-pattern perimeter lengthis: unit of first zone<unit of second zone<unit of third zone<unit offourth zone<unit of fifth zone<unit sixth zone. If there are equalnumber of units per zone, then the rank order applies to zones as well.The change in either open surface area or cut-pattern perimeter lengthacross multiple different zones can be linear, exponential or assume astep-wise or square wave function and be increasing, decreasing,constant, continuous or discontinuous.

In embodiments formed from other cutout segments, e.g., circles orn-sided polygons, the width across any uncut portion, may be varied,i.e., the width may be reduced. This reduction in width will result inan increase in the open surface area 1004. By increasing the opensurface area, the uncut surface area within unit in any one zone, theflexibility of that portion composed of such units with increased opensurface area of the cutout segments will increase.

The portion of the tube wall remaining after the cutout segments areremoved may vary across the length of the tube and is inverselycorrelated with the open surface area of the cutouts. This inversecorrelation is evident from FIGS. 11A-11E which show the cutout patternsof units, white or unmarked, contrasted with the remaining uncut surfaceof the tube, shown in dark color, e.g., black, with stippling. The zonesare labeled as followed: zone 1, FIG. 11A, zone 3, FIG. 11B, zone 4,FIG. 11C, zone 5, FIG. 11D and zone 6, FIG. 11E. As is evident from thefigures, the remaining dark color, e.g., black with stippling or uncutmaterial in the wall of the tube decreases as the open surface area ofthe cutout areas in the unit increases, i.e., the uncut area isinversely correlated with the cutout surface areas. The flexibility ofthe tube may be precisely controlled at any position along the tube bycombining one or more zones at various positions along the length of thetube. Flexibility of the tube is positively correlated with the opensurface area. In other words, as the open surface area of a cutoutsegment increases the flexibility of a zone composed of units having thelarger cutout segments increases. Conversely, flexibility is inverselycorrelated with the uncut area; as the uncut surface area increases,flexibility decreases.

When zones are combined there may be a continuous transition in theremaining uncut area as shown in black across the various zones. Thetotal uncut area at any one point on the tube will depend on a number offactors, including the number of bands in each zone and the dimensionsof the cutout segments (the open surface area of a particular unit). Ifthe number of bands in each zone are constant, then the rank order isfor the uncut surface area, unit of zone 1>unit of zone 2>unit of zone3>unit of zone 4>unit of zone 5>unit of zone 6>unit of zone 7 (in otherwords, there is a fading of uncut area across zones) and the rank orderof flexibility of the tube is zone 1<zone 2<zone 3<zone 4<zone 5<zone6<zone 7 (flexibility is positively correlated with the open surfacearea and inversely correlated with the uncut area). The change inflexibility across multiple different zones can be linear, exponentialor assume a step-wise or square wave function, increasing, decreasing,constant, discontinuous or continuous.

One embodiment where the number of bands of units in each zone are notthe same is shown in FIG. 11F.

A unit in zone 7 is shown in FIG. 12A. The uncut area of the segment inthe unit of zone 7 in FIG. 12 is shown in stripes. In zone 7, the opensurface area 1004 of the cutout segment may be increased as follows. Thecenter of symmetry for the cutout segments comprising A, B, C is 1000.The figure shows portions of three other units from zone 7, 1001, 1002,and 1003. The width across any uncut portion, 1005, 1006, 1007, 1008,1009 (shown only as sample points) may be varied, i.e., the width may bereduced. In one embodiment, the width 1005, 1006, 1007, 1008, 1009 maybe equal. The width 1005, 1006, 1007, 1008, 1009 may be further reducedin a uniform or non-uniform manner. This reduction in width will resultin an increase in 1010 with a corresponding increase in the open surfacearea 1004. By increasing the open surface area, the uncut surface areawithin a unit in zone 7, the flexibility of that portion composed ofsuch units with increased open surface area of the cutout segments willincrease. FIGS. 12B and 12C show photomicrographs with a reduction inwidth of the uncut surface area or strut wall from 10% and 50%,respectively (the dimensions are show in micrometers, μM at the barsshown in the figures). In other embodiments, the reduction in width canbe applied to any zone to increase the open surface area within one zoneor across multiple zones, thereby altering flexibility.

The cutout segment patterns described here can be applied to a varietyof flexible shaft devices, to replace, supplement or be combined withbraiding and coil composite configurations with a single thin walledframe. By using different zone patterns along the shaft length,flexibility can be increased or decreased along the shaft length, aswell as other characteristics of the tube, such as torque, flexibility,pushability, resistance to axial compression and stretch, maintaininglumen diameter and kink resistance.

The cutout segment patterns described here, as well as other cutfeatures of the tube can be made by techniques commonly known in theart, e.g., by a solid-state, femtosecond laser cutting. The tube portionto be cut can be loaded on a mandrel and the relative movement betweenthe laser beam and the tube portion can be controlled by a computer withpre-programmed with instructions to produce any desired cut patterns.Other material removal techniques commonly known would also includephoto-etching, other laser platforms and electrical discharge machining(EDM),

According to embodiments of the present invention, and as shown in FIG.13, a tube 1300 can include a section 1310 that contains one or morezones of the triplex cut patterns described above, as well as a furthersection 1320 that contain other cut patterns, e.g., a spiral cut-pattern1325. The spiral cut section may be longer, equal to or shorter than thetriplex cut patterns. The spiral cut section 1320 may include severalsub-sections that may have different spiral parameters, such as cutwidths, gaps, pitches, etc., such that the bending flexibility along thespiral cut section can vary longitudinally as desired. Additionally, thespiral cut section may also include interrupted spiral cuts 1321 wherethe spiral cuts do not form continuous spirals along the tube wall. Thespiral and interrupted spiral cut patterns are also described inco-pending U.S. application Ser. No. 14/854,242, the disclosure of whichis incorporated herein by reference in its entirety. Either or both ofthe spiral cut section and the triplex section can be encapsulatedwithin an outer jacket and/or an inner lining. The spiral cut may bemade using a laser, e.g., femto-second solid-state cutting laser, byremoving tube material from the tube wall. A tube portion fabricatedwith spiral cuts can also be viewed as a ribbon or flat coil (made ofportions of the remaining tube wall) wound helically about thelongitudinal axis.

The tube may have several different spiral-cut patterns, includingcontinuous and discontinuous. The spiral-cut sections may provide for agraduated transition in bending flexibility. For example, thespiral-cut-pattern may have a pitch that changes the width of the spiralcut ribbon, to increase flexibility in one or more areas. The pitch ofthe spiral cuts can be measured by the distance between points at thesame radial position in two adjacent threads. In one embodiment, thepitch may increase as the spiral cut progresses from a proximal positionto the distal end of the catheter. In another embodiment, the pitch maydecrease as the spiral cut progresses from a proximal position of thecatheter to the distal end of the catheter. In this case, the distal endof the catheter may be more flexible. By adjusting the pitch of thespiral cuts, the pushability, kink resistance, torque, flexibility andcompression resistance of the catheter may be adjusted.

Spiral-cut sections having different cut patterns may be distributedalong any portion of the length of the tube. The spiral-cut patterns maybe continuous (contiguous) or discontinuous along the length of thetube. For example, there may be 1, 2, 3, 4, 5, 6, 7, . . . , nspiral-cut sections along the length of the tube, wherein within eachsection a constant cut-pattern may be present but across differentsections the cut patterns vary, e.g., in terms of pitch. Each sectionmay also contain a variable pitch pattern within the particular section.Each spiral-cut section may have a constant pitch, e.g., in the range offrom about 0.05 mm to about 10 mm, e.g., 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm,0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1.0 mm, 1.5 mm, 2.0 mm, 3.0 mm,3.5 mm, 4.0 mm, etc. The pitch may also vary within each section. Thepitches for different spiral-cut sections may be same or different.Alternatively, the tube may have a continuously changingspiral-cut-pattern along the length of the tube. The orientation orhandedness of spiral-cut sections in the tube may also vary amongspiral-cut sections. Similar to what has been described with respect tocontinuous spiral-cuts herein, an interrupted spiral-cut-pattern canalso have a varying pitch that decreases from a relatively rigid regionto a relatively flexible region.

A tube with triplex cut patterns as described here can be used as aportion of a medical device, e.g., a catheter (which can also bereferred to as a guide catheter extension). One embodiment, of the tubewhich is incorporated into the catheter is shown in FIG. 14. Asschematically shown in FIG. 14A, a catheter 1600 (more particularly, aguide catheter extension) can include a tube portion 1610 (a distal tubeportion) having multiple zones of triplex patterns of varying surfacearea coverage as described above, a skived (angled entrance port) collartransition section 1620 adjacent the distal tube portion 1610 and havinga tapered edge, the taper having a short end 1621 (closest to the distaltip 1609 of the catheter) and a long end 1625 (furthest away from thedistal tip 1609), a push rod (or wire/rail) 1640 being attached orjoined at the long end 1625. In one embodiment, the transition section1620 can be absent, in which case the guide catheter extension includesthe push rod or tube 1640 directly attached to the tube portion 1610.Further, although it is shown that the transition section 1620 includesa straight taper 1623 from the side view, it is understood that variousother shapes for the taper can also be used, e.g., a convex curve, aconcave curve, a curvilinear curve, or other more complex shapes(sinusoidal) (see e.g., the transition sections shown in FIGS. 14A, 15A,15B, 15C), such that a generally slanted lumen opening or mouth isformed which contains a generally decreased, enclosed circumferentialportion along the longitudinal axis L of the catheter away from thedistal end 1609 (at the short end 1621, the enclosed circumferentialportion is nearly 360 degrees, i.e., a full tube, while at the long end1625 the enclosed circumferential portion can be much smaller, e.g.,from 10 degrees to about 50 degrees). The skived transition section 1620and the triplex cut-pattern tube portion 1610 can be made from a same orsingle tube by laser cutting creating a single frame or sections.Alternatively, the tube could be composed of several different frames orsections situated or laid end-to-end about a common center axis. Thepush rod (or wire/rail) 1640, which can be made from a metallicmaterial, such as stainless steel, can be joined with the skivedtransition section 1620 by welding, interlocking or other any otherbonding or fusing method.

FIG. 14B shows a flat or unrolled view of a portion of a guide catheterextension 1700. FIG. 14C shows a photo of the portion of guide catheterextension shown in FIG. 14B. The portion of guide catheter extension1700 includes a tube 1710 having a single triplex pattern (where allunits have the same cutout segments, i.e., the same open surface areaand cut-pattern perimeter length), a skived collar transition section1720 which has a generally tapered edge having a short end 1722 and along end 1725, and an attachment tab 1730 which is welded or bondedtogether with a push rod (wire/rail) 1740. As discussed above, all of1710, 1720, and 1730 can be cut from a single tube by laser. At theshort end 1722 of the transition section 1720, a cut 1715 can be madefrom an edge of the transition section 1720 through a closest triplexunit feature 1712. The width of the cut 1715 can vary. This cut allowsthe tube 1710 to expand or open up under pressure during manufacturingthe catheter assembly when the tube is passed over a mandrel. Thepattern of cuts shown in 1723 can vary. In the embodiment shown in 14B,the pattern forms a square wave pattern with a descending size, i.e.,1731, 1732, 1733, 1734, 1735. In the embodiment shown, when rolled intoa tube, the two square wave patterns come together to form a cage likestructure which is flexible, allowing for entire structure to bemaneuvered through a tortuous path or anatomy.

In one embodiment, transverse cuts made be introduced in the portion ofthe pattern showing the square wave pattern in order to increaseflexibility of the section, 1731, 1732, 1733, 1734, 1735. FIG. 14D. Thewidth of the transverse cuts may also vary depending on the degree offlexibility required. Although schematically, the transverse cuts areshown as lines in the figure, other designs may be used, including asquare wave, sinusoidal or meandering pattern.

As illustrated in FIGS. 15A-15B, the invention provides for a tube 1800(or more particularly, a guide catheter extension) that includes adistal (full) tube portion 1810, a skived collar transition section 1820having a generally tapered edge with varying degrees of an enclosedcircumferential wall portion (forming a slanted lumen opening) which hasa short end 1821 and a long end 1825, and a push rod (wire/rail) 1830connected to the long end 1825 of the skived collar transition section1820. The tube portion 1810 of the catheter can include a generallylongitudinal cut-pattern 1880 such that the side wall of the tubeportion 1810 (and the lumen enclosed therein) can be slightly openedupon an expansion force to facilitate manufacturing of the inner luminalportion of the tube or insertion of an interventional device into theslanted lumen opening of the transition section. Although schematically,the longitudinal cut is shown as a saw tooth line in the figure, otherdesigns may be used, including a square wave, sinusoidal zig-zag,square-wave or meandering pattern; the width of the longitudinal cut canvary and periodicity, i.e., a repetitive pattern is not required. Forexample, the cut-pattern can be a straight line oriented in parallelwith the long axis L of the catheter.

FIG. 15C shows the catheter 1800 where the tube portion 1810 hascut-pattern 1880. The cut-pattern 1880 can start from the short end 1821and can extend either partially or fully along the tube. As illustratedin FIGS. 15A and 15B, the tube portion 1810 may join with another tubeportion 1850 which does not contain a generally longitudinal cutpattern. The tube portion 1850, however, can contain other cut patterns,such as spiral cuts, interrupted spiral cuts, or triplex cut patterns asdescribed herein.

FIGS. 15D-15F show a 3D rendering of the skived collar transitionsection 1820 and the push/rod 1830. The push rod 1830 may be formed froma separate piece and fused to long end 1825 at the junction formedbetween 1832 of the long end 1825 and 1831 of the push rod 1830 by anybonding method, including, crimping, swaging, staking. Adhesive bonding,welding, brazing or soldering may also be used. The design of the jointis shown as a rectangular opening in the long end 1825. Any shape can beused in a lock and key framework so that the push rod 1830 could snapfit into the long end 1825. As shown in FIG. 15F, the profile of thepush rod 1830 is flat with respect to the lumen 1833 formed by the longend 1825.

FIG. 16A shows certain components of a distal portion 1900 of a cathetertube (e.g., a guide catheter extension) according to an embodiment ofthe present invention. FIG. 16B shows the distal portion 1900 asassembled from the components shown in FIG. 16A. FIG. 16C shows apartial sectional view of the distal portion 1900 as assembled; FIGS.16D and 16E show partial views of a portion of the distal portion 1900as assembled near the distal tip (FIG. 16D) and a portion of the distalportion 1900 as assembled away from the distal tip. As shown in FIGS.16A-16E, the distal portion 1900 having a proximal end 1901 and a distalend 1902, and includes a skeletal tubular frame 1910 having a singletriplex cut pattern, an outer jacket 1920, an inner liner 1930, and adistal tip 1940 disposed at the distal end 1902. The term skeletaltubular frame refers to the tube described previously in FIGS.2(A)-(D)-13, inclusive.

The tip portion has a proximal end 1941 and a distal end 1942, where thedistal end 1942 form an inwardly bending curve forming an opening thathas a diameter Dt smaller than that of the lumen Dc of the cathetertube. The distal tip 1940 near the distal end 1942 can include a numberof cuts 1945 to make the distal tip more bendable, i.e., smaller “nosecone” like end in order to minimize trauma of the blood vessel wall whenthe distal tip is being advanced into a patient's vasculature.Alternatively, the distal tip may have a straight tube configuration.The tip portion 1940 can be made from a polymeric material into which aradiopaque material can be embedded or attached. Radiopaque fillersinclude gold, platinum, barium sulfate, bismuth subcarbonate, bismuthoxychloride, bismuth trioxide and tungsten(http://www.fostercomp.com/products/radiopaque-additives, retrieved Nov.1, 2015).

The outer jacket 1920 can be made from a polymeric material, such aspolyether block amide (e.g., PEBA®); the inner liner 1930 can also bemade from polymeric material having improved lubricity, such as PTFE.The jacket can be made from a polymer, e.g., by enclosing the cathetertube with a co-extruded polymeric tubular structure of single ofmultiple layers and heat shrinking the tubular structure, or coating thecatheter tube by dip coating or spraying. See, e.g., US20040142094.Alternatively, the outer jacket can be applied by electrospinning usingvarious polymers, e.g., PTFE to create a fibrous mesh outer layer.

The polymer jacket material can be formed from nylon, polyether blockamide, PTFE, FEP, PFA, PET, PEEK, etc. Further, the distal catheterportion (or the entire length of catheter) may be coated with ahydrophilic polymer coating to enhance increase lubricity when advancingthrough the parent guiding catheter or vascular anatomy. Hydrophilicpolymer coatings can include polyelectrolyte and/or a non-ionichydrophilic polymer, where the polyelectrolyte polymer can includepoly(acrylamide-co-acrylic acid) salts, a poly(methacrylamide-co-acrylicacid) salts, a poly(acrylamide-co-methacrylic acid) salts, etc., and thenon-ionic hydrophilic polymer may be poly(lactams), for examplepolyvinylpyrollidone (PVP), polyurethanes, homo- and copolymers ofacrylic and methacrylic acid, polyvinyl alcohol, polyvinylethers, maleicanhydride based copolymers, polyesters, hydroxypropylcellulose, heparin,dextran, polypeptides, etc. See e.g., U.S. Pat. Nos. 6,458,867 and8,871,869.

The components shown in FIGS. 16A-16E can be assembled by heat shrinkingthe outer jacket 1920 onto the skeletal tube frame 1910, which can fullyembed the uncut or remaining portions of the patterned tube wall, i.e.,the skeletal frame. FIGS. 16E and 16F. The inner liner 1930 can then beadhered with the outer jacket 1920 by heat or other bonding methods(note, the outer jacket is shown with stippling and the inner lining isshown with cross hatching). The inner liner may be incorporated in thecovering process for the outer jacket, but the degree to which it isincorporated is material dependent. As shown in FIG. 16D, the innerliner 1930 can extend distally beyond the distal end of the skeletaltube 1910 and directly fused with the body of the distal tip 1940. InFIGS. 16A-16G, the outer jacket and inner liner are used to encapsulatethe skeletal frame 1910. The skeletal frame 1910 is also bound to theouter most surface of the inner liner 1930, as shown in FIG. 16G.Additionally, dip coating and forming a conformal cover as the outersurface, allows for capturing or embedding the skeletal frame (tube)between the layers thereby creating a composite outer jacket material.The tube itself or the skeletal tube frame can have a triplex, spiral ora combination of patterns or contain linked tubular portions asdescribed here. Once fully assembled with the outer jacket 1920 andinner layer 1930, the interior portion of the tube 1940, i.e., the lumenof the tube, is then completely enclosed within the skeletal tube frame1920, the inner liner 1930 and the outer jacket 1920. The skeletalframe, i.e., the tube, can also be used directly without an outer jacketor inner lining. When using either a coated or uncoated skeletal tubeframe, the driving design factor is maintaining the flexibility of thetube as discussed previously.

The guide catheter extension can include a tube portion 2110 having afully enclosed lumen, a skived collar transition section 2120 adjacentthe distal tube portion 2110 and having a generally tapered edge, and aproximal push rod (wire/rail) 2130 attached to the transition section2120. As illustrated in FIG. 17A, a sealer 2150 can be fitted on thedistal tube section 2110 and near the transition section 2120 to reducethe gap between the guide catheter extension and the surrounding guidecatheter.

The sealer 2150 can take various forms or configurations, as illustratedin FIGS. 17B-17D. As shown in FIGS. 17B and 17C, the sealers 2156 and2157 can be formed with a tubular base 2155 and 2162, respectively, forengaging with the distal tube portion 2110. The sealer 2155 can includea lateral extension or fin 2154 spirally wound about the tubular base2152. Alternatively, the sealer 2157 can include wiping blade surfacescomposed of a single or multiple set of fins or ridges 2164 that arewound circumferentially about the tubular base 2162 (i.e., perpendicularto the long axis of sealer). Alternatively, the sealer 2158 can take theform of a spiral extrusion or filament 2172.

The sealer, 2156, 2157, 2158, can be made with various elastic polymericmaterial, preferably rubbery material having good lubricity, such asPEBA, PTFE, silicon, polyurethane or other fluoropolymers. It can befitted on the distal tube portion of the inner catheter by physicalattachment (e.g., elastic or frictional engagement), chemical bonding,adhering, welding, gluing, heat fused or any other bonding method. Theinner diameters 2155, 2165, and 2175 of the respective sealers 2156,2157, and 2158 can be substantially the same as, or slightly smallerthan, the outer diameter of the distal tube portion of the guidecatheter extension. The fins and the base in sealers 2154, 2164 and2152, 2162, respectively, can be made from the same material, ordifferent materials. The heights of the fins of sealers 2154, 2164, andthe diameter of the spiral wire 2172 can be selected according to theinner diameter of the guide catheter. The outer diameter of thesealer(s) (including the height of the fin(s) in 2154/2164, and thediameter of the spiral wire 2172) can be substantially the same as theinner diameter of the lumen of the guide catheter. The thickness of thefins can be selected such that the fins have sufficient pliability toallow the guide catheter extension to move axially within the guidecatheter without significantly hampering its maneuverability or tactilefeedback to the physician, while remaining sufficient obstructive toimpede flow or back flow of bodily fluids caused by the suction oraspiration on the outer surface of the catheter body.

The guide catheter extension can have a flare or flange 2452. The flareor flange can be used to close or reduce the gap between the guidecatheter extension and an enclosing guide catheter. As illustrated inFIGS. 18A and 18B, a guide catheter extension 2500 can include a tube2410 having a proximal end 2411, which is connected to a push rod 2430.At the proximal end 2411 there is a radially outwardly extending flare2450, that may be substantially perpendicular to the long axis of thetube, which has a greater diameter than the outer diameter of the tubeportion 2410, allowing a seal by a bib 2412 to form between the guidecatheter extension and the guide catheter 2490. In this embodiment, thetube terminates and then transitions directly to the push rod 2430without a transition through a skive.

Alternatively, the guide catheter 2501 can include a distal tube portion2410, a skived collar transition section 2420 adjacent the distal tubeportion 2410 and a generally tapered edge having a short end 2421 and along end 2423, and a push rod 2430 connected to the long end 2423 of thetransition section. A flare or flange 2452 extends radially outwardlyfrom the lumen opening formed by the tapered edge, and has a greaterdiameter than the outer diameter of the tube portion 2410. Thus, likethe sealers described in connection with FIGS. 17A-17D, and the flare orflange described in connection with FIG. 18A, the flare or flange cansubstantially close or seal the gap 2488 by a bib 2435 formed betweenthe guide catheter 2490 and the tube 2410, which may be covered by anouter jacket. This type of construction enables the guide catheter 2490and the guide catheter extension 2500, 2501 to be used to injectcontrast media into a target site in the patient's vasculature withoutleakage from the distal end of the guide catheter, i.e., the end closestto the push rod 2430. The flare together with the bib can also be usedto facilitate smooth insertion of an interventional device, such as aballoon catheter or a stent.

Like the sealer described previously, the flares described in connectionwith FIGS. 17A-17B can be made from an elastic polymeric material,preferably rubbery material with good lubricity, such as PEBA, PTFE,silicon or other fluoropolymers. The thickness of the flare can beselected to ensure the flares have sufficient pliability to allow theguide catheter extension to move axially within the guide catheterwithout significantly hampering its maneuverability. For example, thethickness of the flare can be about 0.1 mm to about 1 mm, or about 0.2mm to about 0.5 mm. The flares can be made as a separate piece andadhered to the proximal end 2411 (in FIG. 18A) or the lumen opening ofthe transition section 2420 (in FIG. 18B), or made as an extension of aninner lining or outer jacket of the catheter extension 2400 a or 2400 b.

In one embodiment, and as illustrated by FIG. 19, the invention providesfor a guide catheter extension 2500 that includes a first tube portion2512, a second tube portion 2514 that has a gradually decreased diameterdistally, and a third tube portion 2516 which is at the distal end ofthe guide catheter extension and that can include a radiopaque tip 2517.The narrowing in diameter of the first and second tube portion may beproduced by shape training of the nitinol tube using standard heatingtechnology (seehttp://www-personal.umich.edu/˜btrcase/share/SMA-Shape-Training-Tutorial.pdf,retrieved Nov. 1, 2015). The skived collar transition section 2520 isdisposed adjacent the first tube portion 2512. The transition section2520 has a generally tapered edge having a short end 2521 and a long end2523, and a flange 2550 extends radially outwardly from the slantedlumen opening formed by the tapered edge. A push rod 2530 is attached tothe transition section 2520.

To use as an injection or aspiration system, both the guide catheter andthe distal tube portion of the guide catheter extension should have atube wall impermeable to fluid. Such impermeable tube wall can be madeof a solid tube (made from a metal, a polymer, optionally with embeddedbraid or other reinforcing material), or made from a tube havingspiral-cut or other cut patterns (such as the triplex cut patternsdescribed herein) and sealed with a fluid-impermeable jacket, e.g.,PEBA, nylon, PTFE, silicon or other material. The invention alsoprovides for an aspiration system including a guide (or outer) catheterhaving a guide catheter lumen, an inner catheter (e.g., a guide catheterextension) movable within the inner guide catheter lumen, and the outeredge of a sealing member on the inner catheter. The inner catheter canbe a guide catheter extension which can generally take the form of thosedescribed herein.

Each of the first tube portion 2512 and the second tube portion 2514 canbe made from a metal or metal alloy (such as stainless steel (springsteel) or nitinol), or a braid or coil supported polymer material. Thesecond tube portion 1514 can include a spiral cut-pattern 2515, and thepitch of the spiral cut can be gradually decreased distally. An outerjacket and an inner lining can be coated onto the spiral-cut section toseal off the openings of the spiral cuts. The third tube portion 2516can be made from a material or construction more flexible or pliablethan the material or construction for the first and the second tubeportions 2512 and 2514. For example, the third tube portion 2516 can beformed from a polymeric material without a wire or braid support. Ingeneral, the flexibility of the three tube portions 2512, 2514, and 2516decreases distally. The flare and the bib together with the distallydecreased lumen diameter allows easy insertion of variable-sized(diameter) interventional devices, such as micro-catheters, ballooncatheters, and stents, into the lumen of the guide catheter extension2500.

The guide catheter extension can be assembled together with a handle forpushing or torqueing. FIG. 20 depicts one embodiment of thenon-functional catheter hub, holding tap or maneuvering hub which canprovide aid in torqueing the device once inside the anatomy, 2608. Thepush rod 2607 is fused to the long end 2600. The lumen 2604 runs throughthe guide catheter extension 2601. In the embodiment shown, there aretwo sealers configurations 2603 and 2062.

The scope of the present invention is not limited by what has beenspecifically shown and described hereinabove. Those skilled in the artwill recognize that there are suitable alternatives to the depictedexamples of configurations, constructions, and dimensions, andmaterials. The citation and discussion of any references in theapplication is provided merely to clarify the description of the presentinvention and is not an admission that any reference is prior art to theinvention described herein. All references cited and discussed in thisspecification are incorporated herein by reference in their entirety.While certain embodiments of the present invention have been shown anddescribed, it will be obvious to those skilled in the art that changesand modifications may be made without departing from the spirit andscope of the invention. The matter set forth in the foregoingdescription and accompanying drawings is offered by way of illustrationonly and not as a limitation.

1-23. (canceled)
 24. A guide catheter extension, comprising: a tubehaving a proximal end, a distal end, a lumen, an inner diameter, anouter diameter, a longitudinal axis, and a skived collar transitionsection positioned at the proximal end of the tube that defines atapered edge, wherein the tube includes a first section having aninterrupted spiral cut pattern therein, wherein the interrupted spiralcut pattern defines a pitch that varies along the length of the section;an elastic polymeric flange extending along the tapered edge of theskived collar transition section; and a push rod having a proximal anddistal end, wherein the distal end of the push rod is attached at ajunction to the proximal end of the tube.
 25. The guide catheterextension of claim 24, wherein the pitch decreases from a proximalportion of the section to a distal portion of the section to provide anincrease in flexibility from a proximal to distal direction.
 26. Theguide catheter extension of claim 24, wherein the outer diameter of thetube tapers from the proximal end to the distal end of the tube.
 27. Theguide catheter extension of claim 24, wherein the push rod is a tube.28. The guide extension catheter of claim 26, wherein the distal end ofthe push rod has a flat profile.
 29. The guide catheter extension ofclaim 28, wherein the push rod is bonded at the junction.
 30. The guidecatheter extension of claim 24, further comprising a tip positioned atthe distal end of the tube, wherein the tip has a proximal and distalend.
 31. The guide catheter extension of claim 30, wherein the distalend of the tip has an inwardly bending curve on an interior surfacethereof.
 32. The guide catheter extension of claim 31, wherein the tipis embedded with radiopaque material.
 33. The guide catheter extensionof claim 24, further comprising an outer jacket at least partiallydisposed on the outer diameter of the tube.
 34. The guide catheterextension of claim 33, wherein the outer jacket is formed from apolymer.
 35. The guide catheter extension of claim 34, wherein theflange is an extension of the outer jacket.
 36. The guide catheterextension of claim 34, further comprising an inner liner at leastpartially disposed within the lumen.
 37. The guide catheter extension ofclaim 24, wherein the flange is adhered to the tube.
 38. The guidecatheter extension of claim 37, wherein the flange is an extension ofthe inner liner.
 39. The guide catheter extension of claim 24, whereinthe pitch of each section is in the range between 0.1 mm and 0.2 mm. 40.The guide catheter extension of claim 24, wherein the pitch of eachsection is in the range between 0.1 mm and 0.3 mm.
 41. The guidecatheter extension of claim 24, wherein the pitch of each section is inthe range between 0.1 mm and 0.5 mm.
 42. The guide catheter extension ofclaim 24, wherein the pitch of each section is in the range between 0.05mm and 10 mm.
 43. A guide catheter extension, comprising: a tube havinga proximal end, a distal end, a lumen therethrough, and a proximalopening to the lumen, wherein the tube comprises a plurality of sectionshaving different cut patterns therein, and wherein the distal end of thetube is more flexible than the proximal end of the tube; a push rodhaving a proximal and distal end, wherein the distal end of the push rodis attached at a junction to the proximal end of the tube; and apolymeric sealer attached to an outer diameter of the tube, wherein atleast a portion of the sealer has a diameter greater than the outerdiameter of the tube, and wherein the sealer is positioned distal to theproximal opening to the lumen.
 44. The guide catheter extension of claim43, wherein the sealer includes an extension or fin extending from anouter surface thereof that is wound circumferentially around.
 45. Theguide catheter extension of claim 43, wherein the sealer includes anextension or fin extending from an outer surface thereof that is woundspirally around the tube.
 46. The guide catheter extension of claim 43,wherein the proximal opening to the lumen is substantially perpendicularto a longitudinal axis of the lumen.
 47. The guide catheter extension ofclaim 43, wherein the tube includes a skived collar transition section.48. The guide catheter extension of claim 43, wherein each section has acut pattern with a different pitch.
 49. A guide catheter extension,comprising: a tube having a proximal end, a distal end, a longitudinalaxis, and a transition section positioned at the proximal end of thetube, wherein the transition section defines an opening orientedsubstantially perpendicular to the longitudinal axis of the tube,wherein the tube further comprises a plurality of sections havingdifferent cut patterns therein, wherein each section has a differentflexibility than the other sections, and wherein the tube has anincreasing flexibility from the proximal end to the distal end; a pushrod, wherein the push rod has a proximal and distal end, and is attachedat a junction to the proximal end of the tube; and a radiopaque tippositioned at the distal end of the tube, wherein the tip has a proximaland distal end, wherein the distal end of the tip has an inwardlybending curve on an interior surface thereof.